Duncan is the Football Correspondent for the Sunday Telegraph and reports on the Premier League, the Champions League and the England national team.

Tottenham are reaping the legacy of Frank Arnesen and Damien Comolli

Tottenham go for the hat-trick on Saturday: first Arsenal, then Chelsea, next Manchester United. Even without Aaron Lennon, their most exciting attacking player, they have seized the initiative for Champions League qualification. It’s exciting stuff.

Their squad is full of young talent with a high market value that, if kept in concert, should continue to improve over the next five seasons. How have they got themselves in such a strong position? One answer is the way Daniel Levy has run the club. Another is that between May 2004 and October 2008 Spurs had continental-style technical directors who radically changed the club’s recruitment strategy.

If Spurs do end up playing in Europe's elite competition next season, they should thank what some might think an unlikely source: Frank Arnesen and Damien Comolli.

Arnesen got the ball rolling, doing a tremendous amount of work in his year at the club. His transfer record was erratic (Tom Huddlestone and Michael Dawson have proved his long-term hits) but he did an important job in altering Spurs’ s attitude to their future. No more hand to mouth – there was now a long-term strategy in place.

Comolli's reputation took a battering at Spurs but history has been kind to him. He left the club in October 2008, along with Juande Ramos, with his transfer record heavily criticised. Harry Redknapp said he had inherited a "mish-mash" of players that did not form a cohesive squad. Yet of the team that started against Arsenal, seven of the players were brought in under Comolli's watch and the other four were already at the club when Comolli arrived.

Redknapp, among the best of man-managers, must take the credit for forging this collection of promising young players into an effective team but the materials he has been working were already in place.

During his time at Spurs Comolli had some clear successes: Dimitar Berbatov, Darren Bent, Didier Zokora and Jonathan Woodgate. He also brought in Luka Modric and Vedran Corluka in the summer before he left, players of evident quality.

Then, though, there were the flops (flop is the word: check the links): Heurelho Gomes, Younes Kaboul, Roman Pavlyuchenko and Kevin-Prince Boateng. Benoit Assou-Ekotto was just not good enough. Another signing, Gareth Bale, was lightweight and went 24 games without being on a winning Spurs team. These players have something in common: they've turned out to be really rather good.

Bale is one of the most exciting young wide players in European football and has been on fire for Spurs. Gomes was heroic against Arsenal and has been the most improved goalkeeper in the Premier League, hoping to get to the World Cup with Brazil. Assou-Ekotto is now first-choice left-back. Kaboul was sold under Ramos and bought back by Redknapp. Pavlyuchenko has emerged as a real force in the second half of the season. And Boateng has inspired Portsmouth to the FA Cup final and will secure a big move in the summer, possibly to Sevilla. Hindsight, eh?

Alan Hutton and David Bentely have not fulfilled their potential but they still have a good market value and have both improved in the last few months. Adel Taarabt (20, on loan at QPR), Chris Gunter (20, now with Nottingham Forest) and Giovanni dos Santos (20, on loan with Galatasaray) may yet still come good. Some, though, definitely did not work: Gilberto, Ricardo Rocha and Hossam Ghaly, by example.

Perhaps most important of all was the work that Comolli did on Spurs' academy. Taking the baton from Arnesen, the Frenchman had Spurs punching above their weight. Danny Rose, the hero of the North London derby, is one of a crop of incredibly promising talents that were brought to the club, including John Bostock, Andros Townsend, Dean Parrett, Paul-José M'Poku and Jon Obika.

It is interesting that Spurs have appointed Tim Sherwood as technical co-ordinator this week. He's bright and engaging and his remit is to integrate these players into the first team, something I’m sure he’ll be very good at. But who is looking for the next Rose or Bostock?

With a new training ground under construction, a stadium to follow, and a squad full of young talent, the future looks promising for Spurs. They already turn a profit, so with increased match-day revenue they could become a serious European force.

The question is, does the belated success of Comolli's signings, and the youth policy consciously implemented in those years, not suggest that having a technical director is not such a bad idea after all? Whatever you might think of Arnesen or Comolli, has the position itself not proved its usefulness? Redknapp's job is to make sure Spurs compete next weekend. He's very good at it. But who is thinking about how Spurs compete in five years' time?